The Clean Air Interstate Rule requires phased-in reductions in the volume of air pollution that states can allow. By 2015, the nation's pollution from nitrogen oxides would be reduced by 61 percent below 2003 levels. Sulfur dioxide pollution would be reduced by 73 percent.
The regulation ''will result in the largest pollution reductions and health benefits of any air rule in more than a decade," said Stephen Johnson, acting administrator at the EPA and President Bush's nominee to be the full-time agency chief.
''The action we are taking will require all 28 states to be good neighbors, helping states downwind by controlling airborne emissions at their source."
The regulations will help states and counties meet new federal standards for healthy air.
The agency said 474 counties around the country have too much smog and 224 counties have too much soot.
The EPA estimates the rule also will prevent 17,000 premature deaths, 22,000 nonfatal heart attacks, and 700,000 respiratory ailments from bronchitis and asthma each year, and reduce haze afflicting parks and forests.
It is up to states to decide how best to achieve the reductions, but the rule envisions that the most cost-effective means is by requiring power plants to install new scrubbers for sulfur dioxide or chemical processes for nitrogen oxides.
''This is going to provide a big boost across the Eastern United States for communities suffering from unhealthy particulate and smog pollution levels," said Vickie Patton, a lawyer for Environmental Defense.
But the rule also is expected to boost consumers' monthly electric bills by at least a few cents more within 15 years.
The EPA said the benefits outweighed costs, dollar for dollar, 25 to 1. By 2015, EPA said, there would be up to $100 billion in yearly health benefits and $2 billion in yearly visibility benefits, compared with about $4 billion in yearly costs.
Homeowners in the United States spend on average about $70 a month for electricity, industry figures indicate. The new rule is not expected to result in significant changes in retail electricity prices between now and 2020, EPA has said.
